2015 Tiffin Phaeton QBH
RV Adjustable bed: Custom King Doppelflex MX2
Two independently operated 2 – motor custom Half – King Adjustable system ( 35.5 X 75 inch) screwed on 72 X 76 inch platform in four places with L-shape brackets. Cut external frame 31.5 inches from the back so that platform can continue to be lifted from the bottom to access storage compartment.
Both adjustable systems are in the “Default mode” where the head section raises initially up to 45 degree angle before the lumbar (back) section then raises to a 65 degree angle.
RV Mattress model: DW 800 Medium Firm (to comfy) Mattress. Two Custom Half King (36 X 76 inch) mattresses.
RV Model: Tiffin Phaeton 2015 QBH
Location: Gainesville, Georgia

Note that the Adjustable bed length was 75 inches so you can see what we had room at the end of the platform that we could have made it an inch longer. However, we played safe in case the system had to be moved down an inch in case the location of the hinge (for lifting the platform for storage access) interfered with the lifting motion.
The hinge location is 30.5 inches from the headboard to the hinge. We cut and removed our external frame 31.5 inches from the top so it would allow the platform to being raised normally for storage access (read more how we do it here:RV Installation Guide)
Above you can see the two adjustable beds side by side, with the left one slightly raised at the foot section. Note that we made the mattress one inch longer so it fit the full 76 inch length of the platform.
The side stopper (hidden) is installed at the head and foot sides to prevent the mattress from sliding off and also the mattress at the head/back section of the adjustable bed would not be held back by the window valence and side table.
Above is the left corner of the mattress that rests on the adjustable suspension.
What a wonderful life!